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Next: wndabs, zwndabs: photo-electric absorption, Up: Multiplicative Model Components Previous: vgabs, zvgabs: gaussian absorption


wabs, zwabs: photoelectric absorption, Wisconsin cross-sections

A photo-electric absorption using Wisconsin (Morrison & McCammon 1983) cross-sections.

$\displaystyle M(E)=\exp[-\eta_H\sigma(E)] $

where $\sigma(E)$ is the photo-electric cross-section (NOT including Thomson scattering). Note that this model uses the Anders & Ebihara relative abundances (1982) regardless of the abund command.

par1=$\eta_H$ equivalent hydrogen column (in units of $10^{22}$ atoms cm$^{-2}$)

The zwabs variant allows the user to specify a (fixed) redshift parameter, and uses the corresponding formula

$\displaystyle M(E)=\exp[-\eta_H\sigma(E[1+z])] $

par1=$\eta_H$ equivalent hydrogen column (in units of $10^{22}$ atoms cm$^{-2}$)
par2=z redshift

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Last modified: Friday, 23-Aug-2024 13:20:40 EDT

HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.